To measure the liquid level in the tanks various industries use different types of level sensors in the tank to measure the liquid quantities using the application as per the requirements.
In this article, we will discuss the different types of industrial level sensors used, their working process, sensor quality, and usage of the sensor in detail.
Capacitive Level Sensors
The capacitive level sensor is used to check the fuel level changes that is being operated by a probe in the sensor. The liquid level changes in the tanks are converted into analog signals and transmitted to the data devices. Usually, the probes are made of conductive wire by Polytetrafluoroethylene (PTFE) insulation.
There is stainless steel probe variation which is highly responsive and that is suitable for the measurement of level changes for non-conductive substances materials.
The capacitive level sensors are easy to use. They are compatible, inexpensive compared to other sensor types, have better accuracy levels, and are invasive to the products. It requires proper calibration and it is suitable for only certain liquids.
These sensors are used in applications such as tank fuel level monitoring for chemical, food, battery, brewery industries.
Optical Level Sensors
The optical sensors work on the light mechanism by emitting the light from the IR LED. It converts the light rays into the electrical signals that measure the light quantity which further translated into a proper measurement.
The sensor is not affected by the temperature and pressure, which is suitable for any condition. This optical sensor can be used to measure any form of liquid as this sensor is small in size.
Since it used optical LED the lens should be taken utmost care of with proper cleaning and maintenance.
This type of sensor is used to measure the liquid in the tank and also detect any leakages that occur in the tank.
Ultrasonic sensors measure the level of liquid using high-frequency sound waves and the distance traveled to and fro from the origin, based on the time duration and strength of the sound waves that are reflected from the liquid.
Sensor mounting on the tank is critical in the ultrasonic type, since the level is measured based on the time travel between the liquid and sensor is critical, the sensor positioning on the tank needs to be taken care of.
Ultrasonic type of sensors are compatible but it is expensive, invasive to materials, at times performance can be affected by different elements. This sensor can be used for highly viscous and bulk solids.
Conductivity Level Sensors
It is also referred as a resistive level sensor. It measures the liquid level that is electrically conducive using the probe to read the conductivity. A pair of electrodes in the probe that applies the alternating current to them.
The major disadvantage of the resistive level sensor is it is invasive and it can sense only conductive liquids.
It is used to measure the tank level for boiling water, corrosive liquids, and reagent monitoring.
Float Switch Sensor
This type of sensor is the most commonly used and cost-effective level sensor to measure the liquid level of the tank. The sensor floats on the liquid, it will raise or low when a liquid is filled or drained out. This is a simple technology with reliable output.
The major drawback of this sensor is it is invasive and has moving parts, at times it can be large in size. It is only suitable to indicate the low and high levels and doesn’t measure the variable quantities.
It is used in the tank level measurement where oil, water, chemical and other hydraulic fluids are used.
Vibrating (Tuning Sensor)
The vibrating sensor may be used to discover overfill or to save you dry-running for applications wherein there is turbulence, air bubbles, or varying products. A fork-fashioned sensing detail with tines is used in this sort of sensor.
The tuning fork sensors are cost-effective and compact, easy to install, invasive to the product, and essentially protection-unfastened.
The vibrating sensors are perfect for stable and liquid stage manipulate, which include foam and sticky substances, as well as first-rate-grained solids and powders. they have indefinite makes use of relying on the fabric that they can feel.
The vibrating sensors are perfect for solid and liquid level control, including foam and sticky materials, as well as fine-grained solids and powders. They have indefinite uses depending on the material that they can sense.
Food, beverage, mining, and chemical processing industries make use of those sensors for their applications.
Radar / Microwave Sensor
The operation of microwave sensors is similar to ultrasonic. But, the pulses tour at the velocity of light, and again; the repeatability and reliability can be exaggerated – however this time with the aid of the dielectric regular of the fluid.
Those sensors ship microwaves by an antenna on the radar sensor. The product it truly is being sensed reflects those microwaves again to the antenna and the time from emission to receiving of the sign is proportional to the extent of the product.
The radar sensors are unaffected via dirt, temperature, or strain. They also can measure pastes, liquids, solids, and powders. These are very accurate and need no calibration. Besides, they’re non-invasive, as they don’t should touch the product it’s sensing.
The radar sensors are costly and have a restrained detection variety. They are even used as a wastewater level sensor to measure the level, sludge, and chemical solutions in sewage remedies.
They’re generally used in programs like moist, vaporous, and dusty environments. They are also applied in systems wherein temperatures range.